Toxic oil syndrome

Toxic oil syndrome (TOS) or simply toxic syndrome (Spanish: síndrome del aceite tóxico or síndrome tóxico) is a musculoskeletal disease. A 1981 outbreak in Spain which affected more than 20,000 people, with over 330 dying within a few months and a few thousand remaining disabled, is thought to have been caused by contaminated colza (rapeseed) oil. It was unique because of its size, the novelty of the clinical condition, and the complexity of its aetiology. Its first appearance was as a lung disease, with unusual features, though the symptoms initially resembled a lung infection. The disease appeared to be restricted to certain geographical localities, and several members of a family could be affected, even while their neighbours had no symptoms. Following the acute phase, a range of other chronic symptoms was apparent.